Phase 2a Safety and Efficacy Data Support Further Development of Oral CC-220 in Patients with Lupus

Celgene International Sàrl, a wholly owned subsidiary of Celgene
Corporation (NASDAQ:CELG), today announced results from the phase 2a
SLE-001 trial evaluating CC-220, the Company's investigational, oral
immunomodulatory compound, at the Annual European Congress of
Rheumatology (EULAR) 2017 in Madrid. A trend toward greater improvement
with CC-220 treatment compared with placebo in multiple measures of
disease activity, as measured by standard scores employed in clinical
trials, was observed in patients with systemic lupus erythematosus
(SLE), commonly known as lupus.

“While the outlook for patients with lupus has improved over the last 75
years, treatment options remain limited,” said Dr. Richard Furie, chief
of Rheumatology at Northwell Health in New York. “New treatment options
are greatly needed for people who are dealing with this often disabling
autoimmune condition.”

The SLE-001 study randomized 42 patients who were diagnosed with lupus
at least six months before and had a baseline SELENA-SLEDAI score
greater than or equal to four. Participants were randomized to one of
four escalating doses of CC-220 (CC-220 0.3 mg every other day, 0.3 mg
once daily, 0.3 mg alternating with 0.6 mg once daily and 0.6 mg once
daily) or placebo for 12 weeks, followed by 12 weeks of observational
follow-up or long-term extension. The study evaluated safety,
tolerability and pharmacokinetics. Efficacy endpoints, including changes
in Cutaneous Lupus Area and Severity Activity Index (CLASI) and
SELENA-SLEDAI score, were exploratory.

The most common adverse events (AEs) were nausea, diarrhea and
maculopapular rash. Serious AEs were reported in two patients in the two
highest CC-220 doses combined (pneumonia in both cases) and in two
patients in the placebo group. Five patients in the two highest CC-220
dose groups and one patient in the placebo group discontinued due to
AEs. No opportunistic infections or other systemic infections were
reported in any CC-220 dose groups.

At day 85, reductions in skin-specific disease activity, as measured by
CLASI, ranged from -4.3 to -7.8 in the CC-220 treatment groups, while a
CLASI score increase of 0.4 was seen in the placebo group. Mean
reductions in CLASI exceeded the minimal clinically important difference
of -4.0 in the CC-220 groups. Additionally, more patients receiving
CC-220 had at least a 4-point reduction in SELENA-SLEDAI score—an index
used to assess lupus disease activity across 24 different disease
descriptors (between 22.2 percent and 50.0 percent for CC-220 vs. 12.5
percent for placebo). A trend toward greater improvement in tender joint
count and swollen joint count was seen in the CC-220 treatment groups
compared with the placebo group at day 85. A trend toward improvement in
the Physician’s Global Assessment score was also seen at day 85 in the
CC-220 groups (ranging from -0.5 to -0.9) compared with the placebo
group (0.0). All data are as observed. The low number of study patients
and some variability in baseline disease characteristics across
treatment groups limit the interpretability of a dose response.

“Celgene is committed to addressing immunological diseases with serious
unmet needs and investigating compounds that we believe could have the
potential to improve the lives of patients. We’re excited by the
possibility that CC-220 may offer a novel mechanism to address lupus, a
complex disease that has few effective treatment options,” said Terrie
Curran, President, Celgene Inflammation & Immunology. “Our work with
CC-220 will also help to diversify and deepen our Inflammation and
Immunology franchise as we continue to advance CC-220 in the clinic.”

CC-220 is not approved for use in any indication in any country.

About CC-220

CC-220 is a novel, oral immunomodulatory compound that binds to and
modulates cereblon, a component of the E3 ubiquitin ligase complex.
CC-220 reduces levels of the transcription factors Ikaros and Aiolos,
which are associated with an increased risk of lupus. CC-220 is
currently being studied in a phase 2 dose-finding study for lupus. It is
also being studied in multiple myeloma.

About Systemic Lupus Erythematosus1,2,3

Systemic lupus erythematosus (SLE), commonly known as lupus, is an
autoimmune disease in which the immune system creates antibodies that
attack the body’s healthy cells and tissues, including joints, skin,
kidneys, heart, lungs, blood vessels and brain. Lupus affects five
million people, mostly women, worldwide.

Symptoms of lupus may vary, but the most common include fatigue, pain or
swelling in joints, muscle pain, skin rashes, hair loss, seizures, sun
sensitivity, ulcers and fever as well as lung, kidney and heart
problems. The disease may have periods without symptoms (known as
remission) alternating with periods of disease flares. There is no cure
for lupus, but medical interventions and lifestyle changes can help
control it.

About Celgene

Celgene International Sàrl, located in Boudry, Switzerland, is a
wholly-owned subsidiary and international headquarters of Celgene
Corporation. Celgene Corporation, headquartered in Summit, New Jersey,
is an integrated global pharmaceutical company engaged primarily in the
discovery, development and commercialization of innovative therapies for
the treatment of cancer and inflammatory diseases through gene and
protein regulation. For more information, please visit www.celgene.com.
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